JGOFS/SMP: Data-Based Models of Food Web Structure and Export Flux

基于数据的浮游生物群落结构和输出通量模型在过去十年中，JGOFS的深入调查表明，物理化学环境强迫，浮游生物群落结构和碳生产的命运（矿化或输出）之间有很强的联系。 然而，现有的浮游生物食物网模型粗略地描绘了这些关系。 目前还不清楚需要多少关于大小和分类组成的信息来进行充分的模型预测，以及不同水团中的群落动态和生物地球化学通量在多大程度上通过共同的组织原则和定量关系联系在一起。透光层碳和相关生物活性物质的生产和出口”。 为实现这一目标，研究所将开发和评估热带/亚热带公海生态系统浮游生物群落结构和输出通量的数据模型。 这一项目将侧重热带和亚热带海洋，这是联合全球海洋观测系统进程和时间序列研究（EqPac、阿拉伯海、热带海洋、最佳可持续发展技术）中最具代表性的领域，目前在成熟数据库和辅助实验研究方面发展最快。 具体目标是：1）发展浮游生物群落结构和营养相互作用的数据约束表示; 2）在夏威夷海洋时间序列（HOT）站点和赤道太平洋铁扰动之后，构建浮游生物群落动态和相关地球化学通量的时间模型（IronEx II）; 3）比较和测试简单的参数化，用于3-D耦合模式中的较低营养级相互作用和输出通量; 4）开发一个通用的热带海洋模式，包括对营养物供应（阿拉伯海）和铁限制（赤道太平洋）的适当反应; 5）检查用于预测计算密集型全球环流模式（GCM）中生物现实反应的模式结构和策略。 根据所观察到的相似性，在不同的热带海洋生态系统的股票和过程率，PI假设，数据将有助于在一个一般的热带海洋模型与共同的结构和参数的代表性。 为了研究在全球模型中捕获基本生物现实所需的最低复杂性水平，他们将统计研究一系列相互关联的模型，所有模型都校准到共同的数据集，但结构复杂性不同。

Data-Based Models of Plankton Community Structure and Export FluxIntensive JGOFS investigations over the past decade have indicated strong links among physical-chemical environmental forcing, plankton community structure, and the fate of carbon production (remineralization or export). However, these relationships are crudely portrayed in existing plankton food web models. It is presently unclear how much information on size and taxonomic composition is needed for adequate model predictions and to what extent community dynamics and biogeochemical fluxes in different water masses are linked by common organizational principles and quantitative relationships.The overall goal of the proposed research is to contribute to the mechanistic understanding of the factors that regulate "euphotic zone production and export of carbon and related biologically active substances". To accomplish this, the PIs will develop and evaluate data-based models of plankton community structure and export flux for tropical/subtropical open-ocean ecosystems. This project will focus on the tropical and subtropical oceans, areas most strongly represented in JGOFS Process and Time-series studies (EqPac, Arabian Sea, HOT, BATS) and presently most developed in terms of mature databases and supporting experimental studies. The specific objectives are: 1) to develop data-constrained representations of planktonic community structure and trophic interactions; 2) to construct models of temporal plankton community dynamics and associated biogeochemical fluxes at the Hawaii Ocean Time-series (HOT) site and following iron perturbation in the equatorial Pacific (IronEx II); 3) to compare and test simple parameterizations, for lower trophic level interactions and export fluxes for use in 3-D coupled models; 4) to develop a general tropical ocean model that includes appropriate responses to nutrient supply (Arabian Sea) and iron-limitation (Equatorial Pacific); and 5) to examine model structures and strategies for predicting biologically realistic responses in computationally intensive Global Circulation Models (GCMs). Based on observed similarities in the stocks and process rates in diverse tropical oceanic ecosystems, the PIs hypothesize that the data will lend themselves to representation in a general tropical ocean model with common structure and parameters. To investigate the minimum level of complexity required to capture essential biological realities in global models, they will statistically examine an interrelated spectrum of models, all calibrated to common data sets but differing in structural complexity.